In the article titled “Fractal Model for Acoustic Absorbing of Porous Fibrous Metal Materials” [1], Figure 12(b) in Section 4.1 (“Experiment and Verification of σ”) is blanked since it is an in-house apparatus of the Institute of Acoustics at the Chinese Academy of Sciences and was published without their permission. In addition, the statement “The inner diameter of the measuring tube is greater than 95 mm and the minimum air velocity can reach 0.5 × 10−3 m/s” should be corrected to “The inner diameter of the measuring tube is 29 mm and the minimum air velocity can reach 0.5 × 10−3 m/s.”
Furthermore, an acknowledgment should be added as follows.
Acknowledgments
The authors would like to thank the Institute of Acoustics at the Chinese Academy of Sciences for providing an apparatus that was used in all the measurement data of resistivity.